1. Field of the Invention
The present invention relates to an incubator.
2. Description of the Related Art
As an incubator used for microbe culturing, food test, etc., an incubator with a heat-insulating and airtight enclosure including a heating means and a cooling means, and configured to control the temperature of a culture chamber to a temperature close to a set temperature by circulating air is known. For example, Japanese Laid-Open Patent Publication No. 2003-47460 discloses an incubator in which a blast fan is switched between rotating clockwise and counterclockwise, depending on a set temperature, to quickly circulate heated or cooled air, and to achieve uniform temperature distribution.
In this manner, by heating or cooling air and circulating it in the enclosure of a heat-insulating, airtight structure, the temperature of the culture chamber is controlled to a temperature close to the set temperature.
A moisture-containing object is placed in the culture chamber of the incubator in many cases, such as in a case of using a liquid culture media. In such a case, a higher culture chamber temperature results in evaporation of a greater amount of moisture, thus leading to an increase in the amount of water vapor in the culture chamber.
Therefore, when an open-air temperature is lower than the dew-point temperature of air in the culture chamber, dew condensation starts condensing on an area showing relatively low heat insulation of the inner surface of the enclosure. For example, dew condensation water is deposited on an observation window of a door, a packing sealing a gap between the enclosure body and the door, etc. If a set temperature drops because of manual setting or programmed automatic setting, dew condensation water may be deposited over a wide range on the inner surface of the enclosure.
This may lead to a situation where dew condensation water corrodes a metal portion of the enclosure or a waterdrop falls onto a culture media to cause contamination.